final drive - Mundo Motorizado

DRS
DECODED
The problem with F1 aero is you can’t see it.
With the help of AUTOSPORT’s CFD drawings,
GARY ANDERSON and JONATHAN NOBLE
shed some light on the dark art of DRS
Downforce on a Formula 1 car is produced by speed
– so the faster you go, the more downforce you
create. As a car goes from 100km/h to 200km/h
it has four times more downforce.
But there is a limiting factor – and that’s drag.
At speed, the rear wing generates a lot of vortices at the
endplate, which the F1 car effectively has to pull along.
This also creates the ‘dirty’ air that makes overtaking
far more difficult.
The solution to that lack of overtaking action was
the introduction in 2011 of the drag reduction system,
which opens the rear-wing flap in a designated zone
when a car is within 1 second of the one in front.
This is what then happens to the airflow…
FIGURE 1 (CLOSED)
You can see here clearly the vortices coming
off the top corners. There is high pressure
on top of the wing and low pressure
underneath it – and there is also static
pressure. When all three of these forces
meet it creates a rotating movement and
that’s getting pulled along with the car.
FIGURE 2 (OPEN)
The main aim of DRS is to get a reduction
in both downforce and drag. When the
wing is open, you can see how much
smaller the vortex is – which means
the wing is doing a lot less work. The
wing is now much more efficient.
32 autosport.com January 31 2013